Liquid treating apparatus



Jan. 23, 1945. A EATQN LIQUID TREATING APPARATUS Filed Feb. 24, 1941 Q Q m\ 3 2 R h 2 m3 1 ME w W m. 9 n m 5 mi w AZ bark E (Lion,

INVENTOR.

ATTORNEY.

Patented Jan. 23, 1945 UNITED STATES PATENT OFFICE LIQUID TREATING APPARATUS Albert Eaton, Garden City, N. Y.

Application February 24, 1941, Serial No. 380,198

3 Claims.

This invention relates to an apparatus for treating liquids, particularly petroleum products, in order to remove impurities therefrom. More specifically, it relates to the treatment of used lubricating oils in a continuous series of batches, by automatically controlled means, to remove dilutents, water, acids, carbon and other impurities so that the oil may be again used.

It is an object of the invention to provide automatically operating means which will feed a series of charges of dirty oil into and through the apparatus and which will not require the continued attention of an operator.

It is another object of the invention to provide an electric control system which will automatically cause the treating apparatus to function in a cycle of predetermined events.

It is still another object of the invention to provide a cycle of events which is controlled in accordance with the condition of the liquid being treated.

Another object of the invention is to provide a filter which can be cheaply operated.

Yet another object of the invention is to provide liquid treating means which will be fully automatic in its operation.

Another object of the invention is to provide a filter which is highly efiicient and which will remove finely divided particles of carbon and other impurities from oils such as crank case oils.

Still another object of the invention is to provide a 'filter which has a low maintenance cost.

Another object of the invention is to provide an automatic, continuous batch filtering process.

These and other objects of the invention will become apparent from a study of the specification and the drawing which is attached hereto and made a part hereof.

The single figure in the drawing discloses the apparatus for treating the oil and has the wiring shovm diagrammatically.

Treating apparatus Referring now to the drawing, numeral I represents the lubricating oil pump of a piece of machinery such as a Diesel engine or the like; 3 represents the discharge line from the pump and 5 is the suction or supply line. A T is provided at I and a dirty oil line 9 is connected by this T to the discharge line of the pump.

The line 9 leads to a second T H from which one branch line l3 connects through a valve l5 into the top of an agitator or slurry tank I! While another branch line l9 connects through an orifice 2 l, a normally closed, solenoid operated valve 23 and a manual valve 24 to a heating or treating tank 25. This orifice is a inch orifice for an oil pressure of forty-six pounds per square inch gage.

By stating that a solenoid valve or other piece of power operated equipment is normally open" it is meant that the device is open when its operator is not energized. Normally closed is employed when the device is closed. V

A source of air under a pressure of about forty pounds per square inch above atmospheric pressure is connected to valve 21 and a T connection 29 has one of its openings connected to the valve 21; another is connected to a line 3| which connects with the interior of the treating tank through an orifice 32 of about one-sixteenth of an overcentersnap switch ll.

an inch in diameter and a normally open, solenoid operated valve 33; while the third opening is connected to a line 35 which contains a pressure reducing valve 31 and a normally closed solenoid valve 39, and which opens into the top of the agitating tank H. The pressure reducing valve reduces the pressure in line 35 to about two pounds per square inch above atmospheric.

The agitating tank I! is provided at its top with an inlet pipe 4| which has a valve 43 in it and which is provided with a funnel 45 at its upper end. This line is used to introduce filter aid and reagents used in the process.

An electric motor 41 is mounted above tank I! and has a shaft 49 which passes through a stufiing box 5| in the top of the tank and has connected to it an agitator mechanism 53 of any r desired construction.

A discharge line 55 leads from near the bottom of tank I! through an orifice fitting 51 and a check valve 59 into the heating tank 25. The check valve is adapted to prevent a fiow from tank 25 into tank [1. and the orifice is proportioned so that it will admit about one gallon of slurry from tank I! into tank 25 while five gallons of dirty oil are passing into tank 25 through the line IS. A one-fourth inch orifice has been used successfully.

Tank 25 is fitted with an electric heater 6| and with a temperature responsive switch 63 which is known to the trade as an Aquastat. This switch is adapted to close at a temperature of about 290 degrees Fahrenheit and to open at a temperature of about 390 degrees Fahrenheit. A float 65 is pivotally mounted at 61 and is connected to a link 69 which passes through a suitable stuffing box and is connected to operate The float is preferably so disposed in the tank that it will open the switch when the tank contains six gallons of oil and slurry. It is, of course, obvious that the volume of the charge may differ from the quantity just stated depending upon the size of the machine.

The tank 25 is fitted with a sump 13 at the bottom, and a discharge pipe leads from this sump, out of the tank and through a check valve 11 which opens upwardly, and thence to a T fitting 19. One branch of the T is connected to an air pressure line 5| through a manually operated valve 83 while the other branch is connected to a line 85 which leads to a T 81.

T 81 is connected by pipe 89 to an L 9| and to a filter 93 while the other branch of the T is connected to a similar filter 95.

Both filters are similarly constructed so that it is necessary to describe only one of them.

Referring to filter 95, it is comprised of complementary upper and lower shells 91 and 99 respectively, which are provided with peripheral bolt flanges IDI, I33 respectively. A perforated plate or screen I05 is mounted between the shells in a manner so as to be clamped between the bolt flanges and a plurality of layers I01 of filter paper, which is preferably ordinary newsprint, is disposed on top of the screen and is also clamped between the bolt flanges. The lower shells of the filter are connected to a filtrate pipe I39 which may be connected either to the engine crank case or any other storage container.

A vent pipe I II is connected to the top of tank and is connected to a cross fitting II3. One branch of the cross is connected to a safety valve II5 which opens to atmosphere at a pressure of, for example, fifty pounds where the air pressure used is forty pounds. Another branch of the cross is connected to a pressure gage II1 while the remaining branch is connected to a normally closed, solenoid operated valve I I9 which also discharges to atmosphere.

A blow-off line I2I is connected to the sump 13 through a manually controlled valve I23 and provides means for discharging sludge to a place of disposal.

Comtrol circuits For controlling and energizing the various power actuated devices, control circuits are provided which function automatically, upon the establishment of various conditions, to cause the required cycle to be carried out and to cause a new cycle to be started when the preceding one is completed.

A main switch I25 is connected to a source of current which for the purpose of simplicity is here designated as direct current.

One circuit extends from the positive pole of the switch I25 through a, manual switch I21, through the Aquastat 53, thence to the winding of a magnetic relay I29 and back to the negative pole of the main switch.

A second circuit extends from the positive pole of the main switch to one lead of the heater GI, thence to a contact I3I of the relay I29, through the armature I33 and thence to the negative pole of the main switch. A signal lamp I35 is connected in parallel across the heater and serves to indicate when the circuit is closed.

A third circuit extends from the negative pole of the switch I25 to the movable contact I36 of the float actuated switch II. In the position of the parts shown, that is with the float down, the circuit continues from the contact I31 to the normally closed, dirty oil valve 23 and back to the positive pole of the main switch.

There is an additional circuit connected in parallel with valve 23 which connects the normally closed, air valve 33 to be energized when valve 23 is energized. This circuit has a secondary parallel circuit through the signal lamp I39 which is used to indicate when the circuit is energized.

A fourth circuit or motor control circuit is connected in parallel with the air valve 39. This circuit comprises a wire I4I leading to one terminal 543 of the motor 41, a wire connecting the other terminal I45 of the motor with the movable pole I41 of a reversing switch, the contact I49 of which is connected by wire I5I to complete the parallel connection. This circuit serves to place the motor 41 under control of the float 65,

A fifth circuit, which is also a motor control circuit, comprises a lead which connects the negative pole of the main switch to the other contact I53 of the motor switch, thence through the mcvable pole I41 thereof, through the motor and thence through lead IM and its connecting wires back to the positive pole of the switch. This circuit will keep the motor 41 running continuously.

A sixth circuit will be established when the float rises. This circuit passes from the negative pole of the main switch I25 to the movable pole I36 of the overcenter switch H, to the second fixed contact I55 thereof, thence to the normally closed vent valve I I9 and back to the positive pole of the main switch. The normally open air valve 33 is connected in parallel across this circuit so that both valves I I9 and 33 are actuated when the circuit is energized.

A seventh circuit extends from the negative pole of switch I25 through the relay armature I51, through fixed relay contact I59 to valve H9 and back to the positive pole of the switch I25. The valve 33 is connected in parallel with valve H9 as described above.

The switch H which is operated by the float 65 is of the overcenter spring type. The contacts- I36 thereof remain out of engagement with contacts I31 and I55 while the float moves from its uppermost to its lowermost position. When the lower position is reached, the contacts are instantaneously brought into engagement and remain thus until the float reaches its uppermost position when the contacts are almost instantaneously disengaged.

The relay I29 is a normally open relay.

Operation Assuming that the apparatus is empty and ready for operation, the main switch I25 is open and the pump I is in operation, the operator will first place in the hopper 45 about two pounds of fuller's earth and two pounds of an activated clay commercially called Retrol. This material is dumped into the agitator tank I1 and valve I5 is opened to admit dirty oil from pump I and lines 9 and I3 until the tank I1 is full, after which valves I 5 and 43 are closed.

The motor control switch I41 is set to close either contact I49 or I53 and the main switch I25 is then closed. This causes the energization of the following elements with their results:

Normally closed dirty oil valve 23 is opened. Normally open air valve 33 is closed. Normally closed air valve 39 is opened. Normally closed vent valve I I9 is opened; Lamp I39 is energized.

Motor 41 is energized.

After motor 47 has run for about three minutes,

' the manually operated dirty oil valve 24 is opened I1 through orifice 51, check valve 59 and pipe 55 1 into the heating tank 25 where it is mixed with the dirty oil being discharged by pump I into tank 25 through valve 23 and orifice 2 I.

The switch I21 may be closed at this time and since the switch 63 is closed, the oil being under 390 degrees Fahrenheit, the winding of relay I29 will be energized to bring armature I33 into en-. gagement with contact I3I to energize the heater 6 I.

The armature I51 also engages contact I59 to set up a second circuit through the air valve 33 and vent valve H9 so as to hold these valves energized when contacts I36, I55 are opened as will be described.

As tank fills, the oil will be heated and the air which is displaced from the tank, as well as any vaporized water or dilutents including the so called light ends, are discharged through the vent valve II 9. The float 65 follows the liquid level when it rises to its uppermost position. The contacts I36, I31 and I55 are broken with the result that the dirty oil valve 23 and the air valve 39 to the mixing tank are deenergized and close. This stops the flow of oil to tank 25.

The valves H9 and 33 are maintained energized because the control circuit through them and the armature I57 and contact I59 of the relay I29 remains closed so long as the relay is energized, and this condition obtains until the mixture in tank 25 reaches a temperature of about 390 degrees Fahrenheit when the contacts in element 63 open to deenergize the relay. During the heating period the volatile impurities are driven out through the vent valve H9.

As soon as relay I29 is deenergized the armatures I 33 and I5! move out of engagement with their respective contacts I3I and I59 with the result that valves 33 and I I9 are deenergized and valve 33 opens while valve I I9 closes.

This effects the application of air at forty pounds per square inch gage pressure to tank 25 and the mixture in this tank is forced out through the pipe I5, through the upwardly opening check valve TI and line 85, 81, 89 and SI to filters 93 and 95. As soon as air pressure is applied to tank 25, check valve 59 closes to prevent back fiow of slurry into tank IT.

The oil which has been purged of water and other volatile substances and also deacidified by the fullers earth and Retrol in heating tank 25 is now passed through the filter papers I01, screen I05, line I99 and is returned to the crank case or storage tank. The fullers earth, Retrol and any other impurities in the oil is deposited on the filter papers in the form of a cake. The

filter aids assist in keeping the cake open so as to greatly lengthen the filtering cycle. The news print paper afiords a filtration medium of such fineness that oil which is black in color is restored in color and brilliance to that of new oil, This has been determined by actual operation of the machine. The oil also is free from dilutents and water.

As the liquid level in the tank 25 falls, the fioat will reach its lowermost position Where it actuates the contacts I36 into engagement with contacts .I3'I'and I55.

As explained above, when these contacts are closed, the valves 23, 33, 39 and II 9 are again energized so that:

Oil valve v23 is opened to admit dirty oil to 25.

Air valve 33 is closed to out off air to 25.

Air valve 39 is opened to admit air to 11.

Vent valve H9 is opened to connect 25 to atmosphere.

The tank is thus refilled with about five parts of dirty oil from the pump I and about one part of slurry from tank I'I.

The element 6|, when it is contacted by rela tively cool oil, again closes to establish the relay circuit and that through lamp I35.

The cycle of operation is thus again begun.

It should be noted that if the motor switch I41 is in engagement with contact I49, the motor will run only so long as the switch II is closed, that is, during the time slurry is being fed into the tank 25,

Tank I'I holds enough slurry for at least one days operation.

Should the pressure in tank 25 rise beyond a predetermined amount, the safety valve H5 will operate to relieve the excess pressure.

When it becomes necessary to clean the filters, the operator may open the main switch which will relieve pressure from tank 25 and he will then open air valve 83. The check valve I I will close and the slurry in lines 85, 87, 89, 9I and filters 93 and 95 will be discharged through the filters after which air can be blown through these lines to dry the cake. When the air is shut off, the bolts may be removed from the bolt flanges, the heads 91 may be lifted and the filter cake and filter papers may be removed.

Upon placing new filter papers on the screen and upon restoration of the filter shells, the apparatus is again ready for operation.

If sludge accumulates in the tank 25, it can be blown off by opening valve I23 at any time that the tank is under pressure.

It has been found by experience that it requires thirty minutes attention from a single operator twice a day to keep the device in operation for an entire day. Its operation is entirely automatic except for the initial charging operation and the replacement of filter papers and removal of cake.

It is obvious that various changes may be made in the form, structure and arrangement of parts without departing from the spirit of the invention. Accordingly, applicant does not desire to be limited to the specific embodiment disclosed herein primarily for purposes of illustration; but instead, I

he desires protection falling fairly within the scope of the appended claims.

What I claim to be new and desire to protect by Letters Patent of the United States is:

1. In a liquid treating apparatus, a treating tank, a heater therefor, a filter, means for discharging liquid from said tank to said filter, and control means responsive to the attainment of a predetermined maximumv temperature of said liquid and a predetermined maximum level of liquid in said tank, for actuating said discharging means.

2. In a liquid treating system, a treating tank, a heater in said tank, a conduit carrying contaminated liquid, means for filling said tank from said conduit, liquid level responsive means having upper and lower positions in which said filling means is rendered inactive and active respectively, temperature responsive means, a filter, means for discharging said tank through said filter, said level responsive means being constructed and arranged to maintain said filling means active and said discharging means inactive during travel of said level responsive means from lower to upper position, said temperature responsive means being adapted to maintain said discharging means inactive until a predetermined liquid temperature is attained.

3. In a'liquid treating system, a treating tank, a heater in said tank, a conduit carrying contaminated liquid, means for filling said tank from said conduit, liquid level responsive means having upper and lower positions in which said filling means is rendered inactive and active respectively, temperature responsive means, a filter,

means for discharging said tank through said filter, said level responsive means being adapted 

